Tear gas and rubber bullets fly in Cairo as police clash with protesters

A protester throws a tear gas canister, which was earlier thrown by riot police during clashes along a road which leads to the Interior Ministry, near Tahrir Square in Cairo on Nov, 22. Egyptians frustrated with military rule battled police in the streets again on Tuesday as the generals scrambled to cope with the cabinet's proffered resignation after bloodshed that has jolted plans for Egypt's first free election in decades.

Khaled Desouki / AFP - Getty Images

An ambulance makes its way through thousands of Egyptian protesters as they attend a funeral of a victim of earlier riots in Tahriri Square on the fourth day of clashes with security forces in Cairo on November 22, as they demand an end to military rule, heightening tension after days of deadly clashes that threaten to derail next week's legislative polls.

Amr Abdallah Dalsh / Reuters

A riot policeman fires a shotgun with rubber bullets at protesters during clashes along a road which leads to the Interior Ministry, near Tahrir Square in Cairo November 22.

Khalil Hamra / AP

Protesters carry a wounded man during clashes with the Egyptian riot police near Tahrir square in Cairo, Egypt, Tuesday, Nov. 22. Egypt's civilian Cabinet has offered to resign after three days of violent clashes in many cities between demonstrators and security forces, but the action failed to satisfy protesters deeply frustrated with the new military rulers.

CAIRO — Egyptians converged on Cairo's central Tahrir Square on Tuesday in response to a call for a so-called "million-man march" as protests against the country's military rulers entered a fourth day.

Thousands of Egyptian protesters have been camping out on the square and clashing with police trying to force them to leave.

NBC's Richard Engel said Egyptian television was reporting three American citizens were arrested after being seen throwing fire bombs from the roof of a building belonging to the American University near Tahrir Square.